Backhoe apparatus

ABSTRACT

A backhoe apparatus or the like having a pivoting column for laterally pivotally connecting a shovel arm to the device. A short operating arm connecting the column to a frame, and an extensible hydraulic cylinder having one end engaging the pivoting column laterally and having another end connected to the operating arm at a point adjacent the frame.

D United States Patent 1191 1 1 3,848,756 Schaeff 1 Nov. 19, 1974 [54] BACKHOE APPARATUS 3,099,358 7/1963 Clark 214/138 c Inventor: H ns schaeff, Wurtt, 7183 3,167,194 1/1965 Davis 214/138 C Langenburt, Germany Primary ExaminerRobert G. Shendan [22] plied: 1973 Assistant Examiner-John Mannix 2 Appl' 337 55 Attorney, Agent, or Firm-Bacon & Thomas Related US. Application Data [62] Division of Ser. No. 125,618, March 18, 1971, [57] ABSTRACT abandoned A backhoe apparatus or the like having a pivoting column for laterally pivotally connecting a shovel arm to [52] US. C1. 214/138 C, 214/131 A the device A Short operating arm connecting the [51] hit. C1 B66f 9/00 umn to a frame,and an extensible hydraulic cylinder 58 Field of Search 214/138 0, 138 R, 131 A having one end engaging the pivoting column laterally and having another end connected to the operating [56] References C'ted arm at a point adjacent the frame.

UNITED STATES PATENTS 2,880,894 4/1959 Walker 2l4/138 c 8 Clams 4 D'awmg F'gures PATENTL 3" 1 W4 SHEET 1 BF 4 INVENTOR.

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HA NS SCI-IA E F F BACKHOE APPARATUS This is a division, of application Ser. No. 125,618 filed Mar. 18, 1971, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a backhoe apparatus, consisting of a frame which can be attached, by hooking, to the carrier vehicle. The attachment is provided with lateral, hydraulically extensible supporting struts and with a pivoting column for pivoting the vertically movable shovel arm laterally.

2. Prior Art In a conventional, simple embodiment of such a shovel the pivoting column is mounted on the frame on an extension of the longitudinal central axis of the carrier vehicle. To pivot the shovel arm in a horizontal plane by an angle of about 180, a suitable, pivoting mechanism supported by the frame is provided. To achieve such pivoting, hydraulic engines with revolving or segmental pistons are known, but they are expensive. Due to internal sealing problems they require frequent servicing. Therefore, it is customary to use as pivoting mechanisms simple hydraulic cylinders engaging both sides of the pivoting column and supported by the frame. However, such cylinders do not produce sufficient torque in all pivoting areas of the shovel arm.

In another widely known shovel embodiment, the pivoting column is mounted on a slide, and is movable transversely to the vehicles longitudinal axis in guides on the frame. Such construction, however, adds to the problems of driving the pivoting column since, due to the mobility of the slide, the pivot drive cylinders must be supported by the slide instead of by the frame. Therefore, it is necessary to provide on the slide above or below the frame, lateral projections on which the hydraulic cylinders are hinged at a sufficient distance from the vertical axis of the pivoting column.

SUMMARY AND OBJECTS It is an object of the invention to provide on the shovel arm or the pivoting column a simple and stable pivoting mechanism with a sufficient torque in all pivoting areas, while retaining the advantage of laterally movable shovels that are capable of digging at a lateral distance and parallel to the longitudinal central axis of the carrier vehicle. An attachable power shovel with backhoe scoop of the aforementioned kind is therefore characterized in that the pivoting column is fastened to the outer end of a short operating arm. A hydraulic cylinder engaging the column laterally is fastened to the inner end of the short operating arm. This arm, in order to pivot a total of at least 90 under the action of a hydraulic cylinder supported on the frame, has its other end mounted on a vertical shaft provided on the frame.

This arrangement offers the advantage that the adjustment of the operating tool at any distance and parallel to the longitudinal central axis of the vehicle can be carried out by simple hydraulic control from the operators cab. The work can then be started immediately after the pivoting, particularly since a mechanical locking is unnecessary. In contrast thereto, in the known laterally movable shovels the slide must be unlocked, laterally moved and then locked again. Furthermore, the transverse movement of known shovels is usually only made possible by placing the arm transversely and trying to move the slide along the guideway on the frame into its new position with the aid of the scoop after the latter is pressed into the ground. However, there is frequently no space for placing the arm transversely, e.g., when working along a wall or in narrow passages.

Use of a short operating arm, as provided by the invention, leads to a simpler construction of the frame which needs to be particularly rigid in its center area only, so as to absorb and transmit forces applied thereto. In known shovels the resistance to rotation of the frame must be assured in any position of the slide, and therefore the slide guide must be relatively heavy. Since in the invention the lateral mobility is produced solely by the additional pivot shaft of the operating arm, substantial savings are achieved in comparison to the work expenditure for the usual two guideways which extend over the frame width.

According to the invention a shaft operating arm is connected and made movable by means of a simple hydraulic cylinder. It is pivotable through an arc of about with sufficient torque, together with the attached pivoting column which is likewise driven by a single hydraulic cylinder with sufficient torque for pivoting the shovel arm with the operating tool approximately 1 10. A total pivoting area of 200 results which when necessary can be increased without difficulties to 220 or 240. The construction of the invention therefore differs from the shovels which are mounted with the pivoting column directly on the frame. It further fulfills the function of the known laterally displaceable shovels and surpasses the latter by having simplified construction, providing more stable structural elements, is more rapid and has more uses.

By using the shaft operating arm, the rear weight of the shovel is theoretically increased. However, this is irrelevant in operation since theshovel is secured by means of the lateral supporting struts. Further, the weight of the rear end is effectively provided only in the center position of the operating arm, whereas in the case of lateral pivoting the same as in the attachable shovels which are laterally movable on a slide. Moreover, the shaft shovel arm offers in the transporation of the shovel the possibility of retracting the shovel arm with the scoop holder and operating tool upward over the frame in order to displace the center of gravity of the shovel approximately to a point above the frame or even further in the direction of the carrier vehicle.

In a special embodiment, the vertical pivoting shaft of the operating arm may be arranged on the side of the frame which faces the carrier vehicle. The frame contains an opening formed by upper and lower' transverse frame elements for positioning and pivoting the operating arm. Thus, the forces can be introduced more favorably from the operating arm onto the frame, while the length of the attachable implement and the rear weight can be kept small. The opening in the frame is suitably formed by vertical lateral box sections with inner walls approximately parallel to the terminal pivot positions of the operating arm and by outer walls connected with the guide tubes of the supporting struts.

In order to produce sufficient support for the arm length achieved by the construction of the invention, outward directed angle plates may be mounted on the outer ends of the upper transverse frame element, for the suspension of the supporting strut hydraulic cylinders. These angle plates are mounted in the path of corresponding slots in the ends of the supporting struts which are extensible upward from the guide tubes. By this construction the upper, extended ends of the supporting struts, even when extended downward, remain in a position covering the whole length of the guide tubes fastened to the frame.

A lever supporting the arm cylinder may be mounted on the transverse shaft of the pivoting column, which shaft supports the shovel arm. The direct pin connection of this lever to a lower fastening ear of the pivoting column is releasable and replaceable, after the pivoting of the lever, by a spacing bar. The lever, which for the transportation of the shovel is pivoted upward about the upper transverse shaft of the pivoting column to an extent corresponding to the length of the spacing bar, offers a new support position for the arm cylinder, wherefrom the shovel holder, including the scoop arm, can be pivoted further upward and back over the frame and possibly also partly over the carrier vehicle.

BRIEF DESCRIPTION OF DRAWINGS The invention is explained in the following description with the aid of an embodiment shown in the drawings, wherein:

FIG. 1 is a side view of the power shovel of the invention;

FIG. 2 is a plan view of the frame, operating arm and pivoting column of the power shovel of FIG. 1;

FIG. 3 is a side view of the constructional unit of FIG. 2; and

FIG. 4 is a partial section of the frame as seen from the attachment side.

DETAILED DESCRIPTION OF THE INVENTION,

The side of a frame which faces the carrier vehicle (not shown) includes upper hooks 11 and a lower transverse shaft 12 for mounting the attachment in corresponding holding devices on the carrier vehicle. The frame consists of upper and lower transverse frame elements 13 and 14 and vertical lateral frame elements 15, 16, which together form a central opening 17. In the center of the side of the transverse frame elements 13, 14 which face the carrier vehicle,upper and lower fastening cars 18, 19 are welded. The ears hold the inside end of an operating arm 20 having a pin 21 therein. On the external walls of frame 10 guide tubes 22 are mounted to carry extensible supporting struts 23. Bydraulic cylinders 24 are fastened at their bottom end within the tubular supporting struts 23 and are hinged on their top end to angle plates 25. The angle plates are in turn welded to the top transverse frame element 13 and directed toward the exterior. The ends of the supporting struts 23, which in the retracted position protrude from the top guide tubes 22 are provided, over a suitable length, with slots or (as shown in FIG. 3) with a recess 26 extending over a portion of their surface. Through the slots angle plates 25 extend into the tubular supporting struts. Guide tubes and supporting struts are preferably (as shown in FIG. 3) inclined in such a manner that supporting recesses 26 in the extended state project from the plane of the frame in the direction toward the operating tool.

Operating arm 20 consists of a welded box structure, e.g., with a cross section shown in plan view in FIG. 2. Operating arm 20 protrudes non-symmetrically to one side approximately to the same extent as fastening ears welded to the other side protrude. A hydraulic cylinder 29 is hinged to a pair of fastening ears 28 provided at the outer end of the operating arm. The piston rod end of this cylinder engages a fastening ear 30 which extends from lateral frame element 16. FIG. 2 shows in broken lines the pivoting area, e.g., of between points A and B, in which area it is moved by hydraulic cylinder 29, retracted in position B and extended in position A. The walls 15a, 16a of lateral frame elements or box carriers which form opening 17 are slanted in such a way as to correspond to the terminal pivoting position of the operating arm.

On the same side as fastening ears 28, but on the inner end of operating arm 20, a pair of fastening ears 31 are provided for holding a hydraulic cylinder 32 whose piston rod end engages a pair of projections 33 of pivoting column 35 which rotates about a vertical shaft 34. The arrangement is such that the cylinder 32 imparts sufficient torque to the pivoting column and to arm 36 fastened thereto, within a pivoting area X of at least Pivoting column 35, which is rotatable about shaft 34 on operating arm 20 and consisting of a welded structure, is provided at its top with a horizontal bearing sleeve 37 to receive a transverse shaft which supports shovel arm 36. This transverse shaft carrier is provided with a lever 38, the bottom end of which is held, by means of a pin in a horizontal bearing sleeve 39 on the bottom side of pivoting column 35. Lever 38 consists preferably of two identically shaped, connected, laterally spaced elements between which arm cylinder 41 is supported at point 40. When, after the termination of the digging, the shovel is to be brought to its position of transportation shown in FIG. 1, scoop 42 is placed on the ground, and cylinder 41 is retracted after the pin connection between the lower end of lever 38 and bearing sleeve 39 has been released. Cylinder 41 moves lever 38 into and out of position shown in FIG. 1 in full and broken lines. Between the lower fastening ear 38a and bearing sleeve 39 a spacing bar 43 is inserted and fixed by fastening pins. From this locked pivoting position of lever 38, arm 36 can be pivoted back upward over the operating arm. It may also be positioned over the carrier vehicle, especially when the operating arm is in its lateral terminal pivoting position. This is discussed in US. application Ser. No. 126,690, filed Mar. 22, 1971 (German application No. P 20 13 849.2 filed Mar. 23, 1970).

An operators seat 51 and a panel 52 with control arm are provided on the top side of operating lever 20 by means of a support 50 extending over frame 10. The arrangement may be such that the operators seat 51 and control panel 52 in the pivoted state of the operating arm leave enough space to make possible the re-- traction of arm 36 near a lateral end of the frame and over this frame until it is on top of the carrier vehicle.

When the arm is retracted over the frame and rests on a support block 44 provided there for transportation, lever 38 can be folded upward by means of cylinder 41 so that traffic obstacles are eliminated.

While there has been described and illustrated specific embodiments of the invention, it will be clear that variations in the details of the embodiments specifically illustrated and described may be made without departing from the true spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. In a backhoe apparatus including a frame, a backhoe boom, a shovel means associated with said boom, a column means at one end of said boom, and an operating arm pivotally connected with said frame for movement about a vertical pivot axis, said operating arm also being swingably connected with said column, whereby said arm is swingable relative to said frame and said column is swingable relative to said arm, the improvement comprising: a first means for laterally swinging said operating arm continuously and under load conditions through an arc of at least 45 to each side of a central position, said first means including a first hydraulic cylinder, one end of which is connected to said frame the other end of which is connected to said arm; and second means for laterally swinging said column independently of the lateral swinging of said operating arm, said second means including a second hydraulic cylinder one end of which is connected to said arm the other end of which is connected to said column, said second means effecting lateral swinging of said boom through an arc of at least 45 to each side of the longitudinal axis of the operating arm, whereby the boom and shovel means are effectively swingable through at least 180.

2. An apparatus as defined in claim 1, wherein said frame includes upper and lower horizontal frame members and at least a pair of vertical frame members, all of said frame members being joined so as to form an opening wherein said operating arm is mounted for movement about said vertical pivot axis, said frame having a first side facing in the same direction in which said operating arm extends from said frame and a second side facing in the opposite direction, said vertical pivot axis being located on said second side of said frame.

3. An apparatus as defined in claim 1, wherein said operating arm is of such length with respect to the width of said frame that, when said arm is swung to either extreme lateral position, the end thereof at which said column is connected will be in a position substantially corresponding to one of the lateral ends of the frame.

4. A backhoe apparatus comprising:

a. a frame;

b. an operating arm swingably connected with said 6 frame; 0. a column swingably connected with said operating arm;

d. a backhoe boom connected with said column for vertical swinging with respect to said operating arm;

e. a first drive means in the form of a single, first, linearly extensible device connected with said operating arm and being the only drive means for swinging said operating arm with respect to said frame, one end of said first linearly extensible device being connected to said frame the other end being connected to said operating arm;

f. a second drive means in the form of a single, second, linearly extensible device connected with said column and being the only drive means for swinging said column with respect to said operating arm, one end of said second linearly extensible device being connected to said operating arm and the other end being connected to said column;

g. whereby said first and second drive means are capable of producing lateral movement of said boom through an effective arc of at least 5. An apparatus as defined in claim 4 wherein said first linearly extensible device is a first hydraulic cylinder having a first extensible piston rod and said second linearly extensible device is a second hydraulic cylinder having a second extensible piston rod.

6. An apparatus as defined in claim 4 wherein both said first and said second drive means are located on the same side of the column and operating arm and are vertically spaced from one another.

7. An apparatus as defined in claim 4 wherein:

a. said operating arm includes an ear extending laterally outwardly therefrom, one end of said first linearly extensible device being attached to said frame, the other end being attached to said ear;

b. said column includes a protrusion extending laterally outwardly therefrom, one end of said second linearly extensible device being attached to said operating arm, the other end being attached to said protrusion.

8. An apparatus as defined in claim 4 including a shovel means attached to said boom. 

1. In a backhoe apparatus including a frame, a backhoe boom, a shovel means associated with said boom, a column means at one end of said boom, and an operating arm pivotally connected with said frame for movement about a vertical pivot axis, said operating arm also being swingably connected with said column, whereby said arm is swingable relative to said frame and said column is swingable relative to said arm, the improvement comprising: a first means for laterally swinging said operating arm continuously and under load conditions through an arc of at least 45* to each side of a central position, said first means including a first hydraulic cylinder, one end of which is connected to said frame the other end of which is connected to said arm; and second means for laterally swinging said column independently of the lateral swinging of said operating arm, said second means including a second hydraulic cylinder one end of which is connected to said arm the other end of which is connected to said column, said second means effecting lateral swinging of said boom through an arc of at least 45* to each side of the longitudinal axis of the operating arm, whereby the boom and shovel means are effectively swingable through at least 180*.
 2. An apparatus as defined in claim 1, wherein said frame includes upper and lower horizontal frame members and at least a pair of vertical frame members, all of said fraMe members being joined so as to form an opening wherein said operating arm is mounted for movement about said vertical pivot axis, said frame having a first side facing in the same direction in which said operating arm extends from said frame and a second side facing in the opposite direction, said vertical pivot axis being located on said second side of said frame.
 3. An apparatus as defined in claim 1, wherein said operating arm is of such length with respect to the width of said frame that, when said arm is swung to either extreme lateral position, the end thereof at which said column is connected will be in a position substantially corresponding to one of the lateral ends of the frame.
 4. A backhoe apparatus comprising: a. a frame; b. an operating arm swingably connected with said frame; c. a column swingably connected with said operating arm; d. a backhoe boom connected with said column for vertical swinging with respect to said operating arm; e. a first drive means in the form of a single, first, linearly extensible device connected with said operating arm and being the only drive means for swinging said operating arm with respect to said frame, one end of said first linearly extensible device being connected to said frame the other end being connected to said operating arm; f. a second drive means in the form of a single, second, linearly extensible device connected with said column and being the only drive means for swinging said column with respect to said operating arm, one end of said second linearly extensible device being connected to said operating arm and the other end being connected to said column; g. whereby said first and second drive means are capable of producing lateral movement of said boom through an effective arc of at least 180*.
 5. An apparatus as defined in claim 4 wherein said first linearly extensible device is a first hydraulic cylinder having a first extensible piston rod and said second linearly extensible device is a second hydraulic cylinder having a second extensible piston rod.
 6. An apparatus as defined in claim 4 wherein both said first and said second drive means are located on the same side of the column and operating arm and are vertically spaced from one another.
 7. An apparatus as defined in claim 4 wherein: a. said operating arm includes an ear extending laterally outwardly therefrom, one end of said first linearly extensible device being attached to said frame, the other end being attached to said ear; b. said column includes a protrusion extending laterally outwardly therefrom, one end of said second linearly extensible device being attached to said operating arm, the other end being attached to said protrusion.
 8. An apparatus as defined in claim 4 including a shovel means attached to said boom. 